Top-seeded Francesca Schiavone was upset 7-5, 6-4 by Miskai Dothe of Japan in the first round of the grass-court Aegon Classic on Wednesday.
Also, Melanie Oudin of the United States defeated Michelle Larcher de Brito of Portugal, 6-3, 6-4, and American Irina Falconi stopped Timea Babos of Hungary 6-4, 6-0.
Schiavone said she's still adjusting to grass after the clay-court season and hopes to improve before Wimbledon and the London Olympics at the All England Club.
''Of course it is upsetting, but it is hard for me, it takes time to adapt to a grass-court rhythm,'' Schiavone said.
She joined several seeded players exiting the Birmingham tournament.
Sixth-seeded Mona Barthel of Germany fell to Andrea Hlavackova of the Czech Republic 7-6 (5), 6-2, and seventh-seeded Christina McHale of the United States lost 6-1, 1-6, 7-5 to Elena Vesnina of Russia.
Jelena Jankovic staved off a bee and two set points in a 6-1, 7-6 (3) win over British wild-card Melanie South.